A major European study conducted by the Coma Science Group (ULg, The University Hospital of Liege) shows that within the medical community, opinions about end-of-life decisions for patients who are in a chronic vegetative or minimally conscious state are influenced by whether or not these patients are believed to be able to feel physical pain. The study was published in the Journal Neuroethics.

The ethical debate surrounding altered states of consciousness is far from over. The debate is all the more delicate in view of the fact that several studies undertaken over the last few years have shown that one in three or even two in five “bedside” clinical diagnoses were erroneous. Thus, some people are declared to be in what is known in today’s terminology as a vegetative state although they are in a minimally conscious state or even in locked-in syndrome (see Immured in a motionless body). Yet, in a minimally conscious state, the patient shows clear signs of consciousness even though these may fluctuate and in locked-in syndrome, their consciousness remains intact in a despairingly motionless body. Moreover, a study conducted by the Coma Science Group of the Cyclotron Research Centre (CRC) of the University of Liege and the Neurology department of the University Hospital of Liege (published in 2008 in The Lancet Neurology ⁽¹⁾) showed that, in contrast with patients who are in a vegetative/non-responsive state, patients who are in a minimally conscious state are capable of feeling pain and emotions; it is therefore necessary to supply them with analgesic medication.

The definition of standardized clinical tools is likely to reduce the incidence of misdiagnosis. The Coma Recovery Scale-Revised – CRS-R, developed in the US by Joseph Giacino’s team at the New Jersey Neuroscience Institute, and validated in French and Dutch by Caroline Schnakers, a postdoctoral researcher at the FNRS, and Professor Steven Laureys, director of the Coma Science Group, pursues this objective. In Belgium, the FPS Public Health imposes its use from now on in all Belgian centres treating patients who have serious brain injury. The work of the Coma Science Group has also made possible the design of a standardized pain assessment scale: the Nociception Coma Scale-Revised.

Diagnosis can be further refined by the use of functional imaging techniques which calls for the design of an easy-to-use, low-cost tool. A lot of work has been done to this end, particularly with the use of the electroencephalogram (EEG) technique and cognitive evoked potentials. The use of functional magnetic resonance imaging (FMRI) and PET scans (see Positron Emission Tomography) in the “resting state” where the subject is awake, with his eyes closed and does not perform any tasks, is also promising.

However, diagnosis of severe brain damage is sometimes a grey area; all the indications are that altered states of consciousness, far from being black and white, are part of a continuum. The ethical debate relative to pain and the end-of-life of patients who are severely brain-damaged exists in itself, independently of the fear of making a diagnostic or prognostic error.

(1) M. Boly, M.-E. Faymonville, C. Schnakers, Ph. Peigneux, B. Lambermont, C. Phillips, P. Lancellotti, A. Luxen, M. Lamy, G. Moonen, P. Maquet et S. Laureys, Perception of pain in the minimally conscious state with PET activation : an observational study, in The Lancet Neurology, 2008.